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The airport capacity problem has recently received a great deal of attention due to airport congestion and delays. Capacity improvements of airfield and airspace component of an airport are currently being addressed by several researchers and federal and state agencies. The optimal location of runway turnoffs is the focus of this research. Although the current airport capacity limitations are dictated by airspace separation rules, it is expected that runway occupancy time (ROT) will become an important factor In the near future as the interarrival separations between landing aircraft are reduced. The intent of this research is to show that the use of high speed exits on runway contributes to the reduction of ROT, and therefore provides enhancement in runway capacity. However, locating the high speed exits is a complex and dynamic problem stemming from the aircraft landing behavior. The landing behavior of an aircraft is affected by many factors such as approach speed, deceleration rate, design exit speed, airport elevation, wind, temperature, etc .. Some of these factors are probabilistic in nature. A simulation model and an optimization algorithm that take into consideration all above factors developed to address the problem. The simulation model consists of a series of dynamic equations of motion that models the aircraft landing behavior under various airport conditions, and determines the best exit location for that aircraft. The optimization model takes the simulation results as input for various aircraft mix, and finds a given number of exit locations which minimize the average ROT for the total aircraft fleet. / Master of Science

Further development of the modern aeronautical and aerospace industries will require increased use of composite materials. It is predicted that the influence of composite materials on the aerospace industry will be revolutionary. Composite materials have many good qualities; however, due to the heterogeneity of their thermal and mechanical properties, they are particularly susceptible to the influences of their thermal environment during manufacture and in certain applications. Therefore, it is essential to be able to perform thorough thermoelasticity analyses of these kinds of materials before they can be considered for certain applications where they will be exposed to high temperatures or steep temperature gradients or thermal shock. Up to now, no results for the transient three-dimensional analysis of the thermoelastic response of fiber-reinforced composite materials, which include the mechanical coupling during a thermal shock, have been reported in the open literature; yet there are a number of practical applications where it might be important to know the thermal-mechanical coupling effects. This thesis serves as a first step toward developing a comprehensive model for the transient thermoelastic behavior of fiber-reinforced composite materials which includes full coupling between the thermal and mechanical processes. / M.S.

This study examines NACA's organization in the light of Alfred D. Chandler's <i>Strategy and Structure</i>. It analyzes the agency's administration. NACA's strategy of maximizing existing technology and its committee's structure were the key elements in its failure to develop jet propulsion in the early 1940s. We will focus first on NACA and its organization. The second chapter will describe jet propulsion, particularly the acquisition of a Whittle engine from England and General Arnold 's role in keeping NACA out of the development of the Whittle engine in the United States. The third chapter will concentrate on the reasons that combined and led to the difficulties of NACA in the mid-forties and the 1950s. That chapter will look at the rise of the aviation industry, the criticism it expressed against NACA, and finally NACA's strategy as one of the causes of failure. / Master of Arts